boost::program_options read an integer array from console

Question

I want to read an integer array from console using boost::program_options. The length of the array is not known and I don't want to read all the data in one attempt. How can I do that?

What I am doing now is

$ ./foo --array "1, 2, 3"

and then populate arr[] by splitting input string.

But I want something like

$ ./foo --array 1 --array 2 --array 3

and read it in arr[]. Also want to know the length of arr[], don't want to make that a command-line param.

Answer 1

Use a vector instead of an array. Then, simply specify a vector as the option type:

po::options_description desc("Allowed options");
desc.add_options()
    ("array", po::value< vector<int> >())
;

Each option on the command line will be appended to the vector.